The result indicate that all of them are toxic to Prodenia litura (Fabricius) and Spodoptera exigwa(Hubner), of them the most toxic to these two kinds of pests are YJ-2000 and CAJ-2 respectively, their LC50 are 57.3044 and 5.5418 mg/L.

• 结果表明这四个菌株对斜纹夜蛾和甜菜夜蛾3龄幼虫均具有毒杀作用；YJ-2000对斜纹夜蛾杀虫活性最高；LC_(50)为57.；3044mg/L；CAJ-2对甜菜夜蛾杀虫活性最高；LC_(50)为5